516 HEAT OF THE GILA VALLEY. Book III 
convinced me of the fact. It is well known even in Europe 
that an attempt tending in that direction, and ending still 
more unfortunately than the two previous ones, has been 
made after the time of my passing through the country. 
We broke up our camp in the evening • but, in spite of 
the late hour, the wind met us hot from the rocky desert 
through which we had to pass. We had suffered from the 
heat all along the Gila. I had no thermometer with me, 
but it is well known that the summer heat of these regions 
ranges from 100° to 120° Fahrenheit in the shade. But the 
effect of this high temperature upon the body must be esti- 
mated by the dryness and the rocky character of the soil, 
rather than by the scale of degrees. The ground was so 
hot that if our mules stood still for a minute or two, they 
twitched up their feet in evident pain, and even after mid- 
night I could not sit down on the rock with comfort. Our 
Mexican drivers during this journey would sit the greater 
part of the night, naked upon their mules, and yet were 
bathed in perspiration. Towards morning alone, was the 
slightest degree of coolness to be perceived. The shade, 
during the day, brought no refreshment, and wind increased 
the scorching heat, by adding fresh supplies, instead of 
lessening them. I was obliged one day, lower down the 
valley, to go about a mile in the river, in search of some 
missing mules ; and the water was as hot as that of a 
very warm foot-bath. Whenever I came upon a dry sand 
bank, I found it too hot to bear more than a few steps 
upon it,* indeed I am sure that 100 steps would have 
blistered my feet. 
The old chief of the Pimas, whose authority is recog- 
nized by the Cocomaricopas, and whose name, whether, 
according to some travellers, it may be Cola Azul, or, 
according to others, Culo Azul, has an equally inexpres- 
